Cover for suction box of paper machines



y 12, 1955 A. P. WAGENKNECHT COVER FOR SUCTION BOX OF PAPER MACHINES 2 Sheets-Sheet 1 Filed Aug. 13, 1955 INVENTOR.

July 12, 19 A. P. WAGENKNECHT 2,712,776

COVER FOR SUCTION BOX OF PAPER MACHINES Filed Aug. 15, 1953 2 Sheets-Sheet 2 IN V EN TOR.

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United States Patent 0 2,712,776 COVER FOR SUCTION BOX OF PAPER MACHINES Arthur P. Wageuknecht, Pittsfield, Mass. Appiication August 13, 1953, Serial No. 374,009 5 Claims. (Cl. 9251) This invention relates to improvements in paper making apparatus and is directed to improvements in the cover or plate for a suction box.

A suction box of a paper machine is a receptacle connected to a source of suction and has an upper perforated cover or plate over which the Fourdrinier wire travels. The wire carries paper making fibers suspended in water and the suction box functions to pull the water through the wire.

Speeds of paper machines are ever increasing and the demands are for wider machines which require longer suction boxes, and increased suction box efiiciency.

The principal object of the invention is the provision of a suction box cover or plate which is adapted for high speed operation and the increasing widths of paper machines.

water elimination and more or less, in order to operate efliciently, limit the speed of the Fourdrinier wire. Also they do not withdraw water uniformly across the width of the wire which affects formation of the paper web.

According to this invention, a cover is provided which is not only adapted for high speed operation but water extraction is uniform across the Wire to facilitate uniform web formation.

This is accomplished in a general way by the provision of elongated slots in the cover plate extending therethrough which are disposed angularly relatively to the direction of wire travel. Said slots extend downwardly in the direction of travel of the Fourdrinier wire to facilitate rapid water withdrawal. That is, the slots being angularly disposed as they are, the far edges thereof function with a shearing action with relation to the Wire to enhance rapid water elimination. Said edges of the All of the above objects I accomplish by means of such structure and relative arrangements of parts thereof, as

will fully appear by a perusal of the description below and by various specific features which will be hereinafter set forth.

To the above cited and other ends and with the foregoing and various other novel features and advantages and other objects of my invention as will become more readily apparent as the description proceeds, my invention consists in certain novel features of construction and in the combination and arrangement of parts as will be hereinafter more particularly pointed out in the claims hereunto annexed and more fully described and referred to in connection with the accompanying drawings wherein:

Fig. l is a plan view of a suction box cover plate embodying the novel features of the invention;

Fig. 2 is an end elevational view of the cover plate shown in Fig. 1;

the wire.

Fig. 2A is a partial plan view of a modified form of the suction box cover shown in Fig. 1;

Fig. 3 is an enlarged partial plan view of the cover plate shown in Fig. 1; and

Fig. 4 is a sectional elevational view on the line 4-4 of Fig. 3.

Referring now to the drawings more in detail, the invention will be fully described.

A cover plate is represented by 2 which will preferably be formed from a laminated plastic, metal, or other suitable material.

It will be understood that the plate is secured in the ordinary manner to the upper open side of a suction box which has outlet means connected to a source of sucnon.

paper making material is withdrawn through the wire for elimination thereof.

Groups or sets of elongated slots such as slots 4 and slots 6 extend through the plate from upper to lower face the slots at the opposite right hand end of the plate, as Preferably the slots will be of equal transverse The slots incline downwardly from their upper entrances.

water elimination, there being no tendency of Water backing up since water moves downwardly of the slots in the direction of the wire travel.

Not only does the angular disposition of the slots enhance water elimination, but also the far edges thereof case were the slots parallel to the transverse elements of Thus the life of the wire is prolonged. The set of slots at one end of the plate extend in a di- The relative arrangement of the slots is such that along any line transversely of the plate or in any transverse plane the total area of slot openings is the same as that along any other line or plane. That is, the total area of slot openings along the dash line b of Fig. 3 is the same as along the dash line c of Fig. 1.

Such an arrangement provides for uniform suction throughout the length 'of the cover plate and transversely of the wire for improved and uniform paper formation.

in the modified form 'of a cover plate represented by 2 as shown in Fig. 2A, groups or sets of elongated slots 6 extending through the plate are provided. The slots may be divided into two or more sections such as shown.

As in the case of the form shown in Fig. l, the slots incline downwardly and forwardly from their upper entrances. The slots incline downwardly and forwardly in the direction of travel of cated by arrow a and opposite ends of all the slots extend in parallelism and in parallelism with the direction of travel of the wire.

The invention may be embodied in other specific forms without departing from the essential characteristics thereof. Hence, the present embodiments are therefore to be considered in all respects merely as being illustrative and not as being restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all modifications and variations as fall within the meaning and purview and range of equivalency of the appended claims are therefore intended to be embraced therein.

What it is desired to claim and secure by Letters Pa.- ent of the United States is:

.1. A cover for a suction box of a Fourdrinier paper machine comprising, an elongated plate having upper and lower faces and parallel longitudinal forward and rear edges for supporting a Fourdrinier wire moving transversely across the plate from forward to rear edge thereof, said plate provided with a set of relatively spaced parallel slots having parallel opposite sides and extending through said plate and being disposed angularly relative to the edges thereof and the direction of movement of said wire thereacross and having opposite ends terminating inwardly of said edges, said slots being inclined forwardly from the upper face and forward edge to the lower face and towards the rear edge of the plate, and each said slot having opposite ends thereof in parallelism and at right angles to the longitudinal edges of the plate.

2. A cover for a suction box set forth in claim 1 wherein said slots are arranged so that in any plane from edge to edge of the plate and at right angles to the faces thereof the Fourdrinier wire, indi-' 4 the slots in said plane are of the same total area as the total area of slots in a similar plane parallel thereto.

3. A cover for a suction box of a Fourdrinier paper machine comprising, an elongated plate having upper and lower faces and parallel forward and rear longitudinal edges, said plate provided with sets of relatively spaced slots, the slots of the sets thereof extending through said plate from the upper to the lower faceof the plate and towards the rear edge from the forward edge, the slots of the sets thereof being in parallelism and the slots of each set thereof being disposed angularly relative to the edges of said plate and the direction of movement of a Fourdrinier wire thereover with the slots of one set being in a direction opposed to the direction of the slots of the other set and each slot having opposite ends disposed at right angles relative to the edges of said plate.

4. A cover for a suction box set forth in claim 3 wherein said slots are arranged so that in any plane at right angles to the faces of the plate and from edge to edgethereof the total area of slots is the same as in any other plane parallel thereto.

5. A cover for a suction box of a Fourdrinier paper machine comprising, an elongated plate having upper and lower faces and forward and rear longitudinal edges, rows of relatively spaced elongated slots extending through said plate, the rows of slots being in spaced parallel relation and extending angularly relatively to the edges of said plate with the ends of the slots of one row being staggered relative to the ends of the slots of an adjacent row, said slots extending from upper to lower faces of the plate and in a direction from forward to rear edge of said plate and opposite ends of said slots being in parallelism and at right angles to the edges of said plate, said slots arranged whereby the total area of slots in a plane at right angles to the faces of the plate from edge to edge thereof is the same as in another plane parallel to said plane.

References Cited in the file of this patent 

